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121.
Saeedeh Golharani Sajad Jahanbakht Azam Moeini-Nashalji 《Waves in Random and Complex Media》2018,28(3):488-507
In this paper, a plasma waveguide made of two eccentric cylindrical metallic walls have been studied according to the theory of transmission lines. The inductance per unit length L, the capacitance per unit length C, the resistance per unit length R and the shunt conductance per unit length G are obtained. The graphs of variations of the mentioned parameters vs. geometrical dimensions of waveguide are investigated. This investigations have been done for two different types of plasma waveguide. At first stage, plasma region will be considered in cold and collisional approximation and in second stage, a drift plasma in cold collisionless approximation will be considered. Also, graphs of phase velocity variation vs. the main parameters of the waveguide are presented. 相似文献
122.
Effect of the structure-directing agent on the floral (depicting flower) morphological variation of ZnO is systematically studied and presented here. Flowery decorated (resembling flower) zinc oxide structure composed of hexagonal nanorods (sharp tips and wider bases) was synthesized at 90 °C using zinc acetate dihydrate and sodium hydroxide at various concentrations of hydroxylamine hydrochloride for 12 h by solution method. Single crystalline nature with the wurtzite hexagonal phase remained unaltered with increasing concentration of hydroxylamine hydrochloride while the morphology changes from nanorod to plate like structure. Photoelectron spectroscopic measurement presented spectra close to the standard bulk ZnO, with an O 1s peak composed of surface adsorbed OH group, O2− in the oxygen vacancies on ZnO structure and ZnO. At higher concentration (0.8 M), surface adsorbed OH group increases while other component decreases because of the changes in the nucleation and surface energy. Results clearly indicate that hydroxylamine hydrochloride works as a structure-directing agent without affecting other properties. 相似文献
123.
Zafar Ali Khan Khattak Zia‐ur ‐Rehman Azam Khan Afzal Shah Waqar Zaid Amin Badshah Mohammed Fettouhi Atif Fazal 《Heteroatom Chemistry》2014,25(4):238-244
This article presents a new heteroleptic Zn(II) dithiocarbamate ( 1 ) having molecules linked together via H···H and π···π interactions to form a giant hexanuclear macrocycle. These macrocycles are connected together through S···H interactions to offer a unique two‐dimensional cloth‐like interwoven architecture in the solid state. The redox behavior of the complex deposited on the surface of a glassy carbon electrode was investigated in different pH media. The analyte was found to oxidize and reduce in a pH‐dependent irreversible manner. On the basis of the electrochemical findings, redox mechanistic pathways were proposed. 相似文献
124.
Muhammad Sagir Isa M. Tan Muhammad Mushtaq Lukman Ismail Muhammad Nadeem Muhammad Rizwan Azam 《Journal of Dispersion Science and Technology》2014,35(3):463-470
The synthesis of novel CO2 philic surfactant using maleic anhydride and dipropylene tertiary butyl alcohol is reported. The synthesis involved the esterification of maleic anhydride to produce bis(2-(2-(tert-butoxy)propoxy)propyl) maleate and subsequent sulfonation of the esterified product. Para toluene sulfonic acid was employed as catalyst for the esterification reaction. The esterification reaction was optimized for the maximum yield of 98% of bis(2-(2-(tert-butoxy)propoxy)propyl) maleate. The esterification reaction kinetics employing heterogeneous catalyst were also studied. Although this is a bimolecular reaction, a first order reaction kinetics with respect to acid has been observed. The activation energy was found to be 58.71 kJ/mol. The diester was followed by the sulfonation process and a yield of 85% of surfactant was achieved. The synthesized surfactant successfully lowered down the IFT between CO2/brine to 1.93 mN/m. This surfactant has a great potential to be used for CO2-EOR applications. 相似文献
125.
N.K. Piracha K.V. Duncan-Chamberlin M.A. Kalyar Rizwan Ahmed 《Optics Communications》2011,284(12):2872-2875
Using neon hollow cathode lamp and employing laser optogalvanic technique, we have studied population redistribution in the 2p53p multiplet. The spectra recorded in the laser energy region of 23300 cm− 1 -23600 cm− 1 show transitions originating from both the laser excited levels as well as from an adjacent level whose population builds up as a result of collisional deactivation. Employing the optical delay technique, we have been able to extract decay rates associated with the collisional population mixing of the p levels. 相似文献
126.
127.
Ijaz F. Shafqat S. S. Babar R. Rizwan M. Zafar M. N. Khan M. A. Munawar M. A. 《Russian Journal of Organic Chemistry》2020,56(3):509-513
Russian Journal of Organic Chemistry - A fine, green, and efficient method has been proposed for the synthesis of 2-aryl-4,5-diphenyl-1H-imidazoles using various sugars such as glucose, fructose,... 相似文献
128.
Structural Chemistry - Enterococcus faecium MurF (EfMurF) enzyme catalyzes the addition of d-alanyl-d-alanine to form murein UDP-N-acetylmuramoyl-pentapeptide. This is the last cytoplasmic step of... 相似文献
129.
This paper is a report on the development of a convenient approach to fabricating a very efficient hybrid photoelectrocatalyst for water splitting.This photoele... 相似文献
130.
Mahmood Z Azam M Mushtaq A Kausar R Kausar S Gilani SR 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,65(2):445-452
The infrared spectra of pure Mn(CO)(5)X in the region 4000-400 cm(-1) has been obtained in the vapour phase. The observed spectrum has been analyzed to distinguish the fundamental frequencies, the rotational-vibrational and structure, and overtone and combination frequencies. The assignment of the observed vapour phase frequencies to the fundamental modes of vibration has been made on C(4V) symmetry. The weak peaks due to XMn(CO)(4)((13)CO) molecules have been measured and assigned for all molecules. This study provides a comprehensive comparison of these compounds, with all of these data the assignment of frequencies is reviewed and a set of quite unambiguous assignments made. The significant finding in this regards are that, it is not necessary to assume lower than C(4V) symmetry for XMn(CO)(5) as has been done in previous consideration of some infrared spectrum of these compounds. 相似文献